Square Four tyre pressures?

Singles, twins and fours.
User avatar
john.bebb
Holder of a Nylon Anorak
Holder of a Nylon Anorak
Posts: 149
Joined: Mon Sep 02, 2013 1:29 pm
Location: Frinton on Sea, Essex, UK
Contact:

Square Four tyre pressures?

Postby john.bebb » Thu Apr 10, 2014 7:30 am

Hi Folks; - please can anyone advise on the recommended tyre pressures for a Mk1 (1949) Square Four? - thank you.

User avatar
adrie.degraaff
Holder of a Golden Anorak
Holder of a Golden Anorak
Posts: 2979
Joined: Sun Feb 27, 2011 10:07 am
Location: Holland
Contact:

Re: Square Four tyre pressures?

Postby adrie.degraaff » Thu Apr 10, 2014 8:00 am

It is depending on your tires, some have the pressure writen on it.

User avatar
markus.nikot
Holder of a Nylon Anorak
Holder of a Nylon Anorak
Posts: 219
Joined: Sun Feb 27, 2011 11:18 am
Location: Frankfurt, Germany
Contact:

Postby markus.nikot » Thu Apr 10, 2014 10:15 am

I'm running mine with 2,5bar, Avon Speedmaster

Markus
AOMCC German Branch Secretary
some Ariel - only Ariel

User avatar
john.bebb
Holder of a Nylon Anorak
Holder of a Nylon Anorak
Posts: 149
Joined: Mon Sep 02, 2013 1:29 pm
Location: Frinton on Sea, Essex, UK
Contact:

Postby john.bebb » Thu Apr 10, 2014 10:34 am

Hi Markus -both front and back?

nevhunter
Holder of a Golden Anorak
Holder of a Golden Anorak
Posts: 3976
Joined: Tue May 10, 2011 9:42 am
Location: Victoria.. Australia.
Contact:

Postby nevhunter » Thu Apr 10, 2014 12:47 pm

Bar is 14.7 psi 2 bar should be enough. Tyre section makes a difference. The bigger the less pressure required. Nev

User avatar
brenton.roy
Holder of a Golden Anorak
Holder of a Golden Anorak
Posts: 2056
Joined: Sun Feb 27, 2011 1:13 pm
Location: Adelaide, South Australia
Contact:

Postby brenton.roy » Thu Apr 10, 2014 1:37 pm

John, I think it depends on how you want the bike to feel. The 4.00 rear tyre was big for its time and I suspect it was run at low pressure for the softer ride that would give. I think this is also the reason for the 'wallows at speed' comments about square fours in old road tests. 30psi is a good starting point with new tyres.
'51,'56 Squares, '48 VH, '27 Model C, R67/2, Mk IV Le Mans, '06 Super Duke and Ariel projects.

User avatar
john.bebb
Holder of a Nylon Anorak
Holder of a Nylon Anorak
Posts: 149
Joined: Mon Sep 02, 2013 1:29 pm
Location: Frinton on Sea, Essex, UK
Contact:

Postby john.bebb » Wed Apr 23, 2014 12:50 pm

Hi All; - I settled for 32f 36r - zero tail wallow but a bit harsh on the front -so I'll try it on 30f.
Dunlop "Roadmaster" TT100's

Thoward
Posts: 5
Joined: Sat Mar 14, 2020 11:40 am
Contact:

Re: Square Four tyre pressures?

Postby Thoward » Sun May 10, 2020 10:48 am

Hi, I inflated to 30psi in the front and 32psi in the back, seems ok with normal riding on the A184 in Essex. I only weigh 10 stone, so depends on the load I guess. I have Avon speed-masters fitted, in good condition, well, almost new in fact.
Cheers

User avatar
john.bebb
Holder of a Nylon Anorak
Holder of a Nylon Anorak
Posts: 149
Joined: Mon Sep 02, 2013 1:29 pm
Location: Frinton on Sea, Essex, UK
Contact:

Re: Square Four tyre pressures?

Postby john.bebb » Sun May 10, 2020 11:34 am

Hi Folks,
A few further thoughts on tyre pressures; - modern tyres are built to a far more advanced structure than those back in the 30's thru 50's.
Materials, construction & tread patterns have changed as also have the majority of road surfaces... (some of these have not stood the tests of time quite so well as some of our motorcycles!... nor are some roads maintained as one might hope...).
As an additional guide as to what pressurese are correct - take it for a long (>50mile) & dry reasonably hard drive... the moment you park up at the end; - gloves off & cup your hands over the treads - both should be slightly warm & tacky - neither stone cold nor "Ouch" too hot. Front should be slightly cooler as it's not involved so much in power transmission...
Such is only a guide and I politely remind all that measured tyre pressures are only relevant when measured cold - before vehicle use!
Cheers, John.

allan.walker
Posts: 64
Joined: Fri Sep 28, 2018 8:35 am
Contact:

Re: Square Four tyre pressures?

Postby allan.walker » Fri May 15, 2020 10:07 am

Another point regarding modern tyre compounds. From what I have seen, modern tyres seem to need higher inflation pressures than the motorcycle manufacturers recommended in their handbooks in the 50's and 60's.

Therefore, it pays to go on the tyre manufacturers website and check the pressure ranges that they advise.


Return to “Four stroke”

Who is online

Users browsing this forum: No registered users and 9 guests